Aspen Matthews sketch

Well... last saturday, I bought something i wanted to by a very long time.. i finally got a big wacom tablet! got myself a wacom intuos3 a5 wide tablet and i wanted to do a warming up, getting used to the tablet and all.. so i did this sketch of aspen that michael turner did.. it seemed appropriate.

the hair is bugging me, i tried to do something new, and i made progress over how i used to color hair, but its still far from where i want it to be.. so any tips or critiques are welcome! other than that, i like how it turned out and my tablet is awesome..